Combined seatback frame



FIG. 1 is a front view of the combined seatback frame;

FIG. 2 is a rear view of the combined seatback frame;

FIG. 3 is a left view of the combined seatback frame;

FIG. 4 is a right view of the combined seatback frame;

FIG. 5 is a top view of the combined seatback frame;

FIG. 6 is a bottom view of the combined seatback frame; and,

FIG. 7 is a perspective view of the combined seatback frame. 

The ornamental design for a combined seatback frame, as shown and described. 